<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
<div id="app">
    {{ school.name}}
    {{ school.age}}
    {{ school.address}}
</div>

</body>
<script src="../node_modules/vue/dist/vue.js"></script>
<script>
   let vm =  new Vue({
        el: '#app',
            data:{
                school:{name:'',age:8},
                msg:'hello!'
            }
    })
//    vm.$set(vm.school,'address','test')
//    vm.school = Object.assign({},vm.school,{address:'test2'})
    vm.school = {...vm.school,...{address:'test3'}}
</script>
</html>